This invention relates to cutters for cutting fabric and other similar flexible sheet material spread on a supporting surface, and deals more particularly with such a cutter using a rotary cutting blade as the cutting tool and having associated with it an improved sharpening mechanism for sharpening the edge the blade while the blade remains in the cutter.
Copending U.S. patent application Ser. No. 736,839, entitled "APPARATUS AND METHOD FOR SUPPORTING AND WORKING ON SHEET MATERIAL", filed May 22, 1985, and assigned to the same assignee as this application, discloses a cutting machine using a cutter of the type to which this invention pertains, and reference may be made to that application for further details of the overall cutting machine and system. As to the cutter itself, however, it uses a relatively small diameter circular cutting blade rotated at high speed about a horizontal axis and moved along desired lines of cut with respect to work material spread on a horizontal support surface, the cutter blade also being rotated about a vertical theta axis during such movement to maintain it tangent to the line of cut. As the cutting progresses, the cutting edge of the blade inevitably becomes worn or dulled and it is therefore desirable to provide some means for sharpening the blade from time to time without having to remove the blade from the cutter for the sharpening procedure, and also preferably without having to stop the cutting procedure when the sharpening occurs. That is, it is desirable to be able to perform the sharpening "on the fly".
In the past various different sharpening devices have been proposed for sharpening rotary cutting tools, but in general these have been of relatively complicated construction, often they are not productive of a good sharpening effect and in most cases they are not such as to lend themselves well to use with a small cutter blade having a diameter on the order of one inch or less.
The general object of this invention is therefore to provide a rotary blade cutter for fabric or similar sheet material including a sharpener for periodically sharpening the cutting edge of the blade, which sharpener is of simple, low cost construction, reliable in operation, productive of an excellent sharpening effect, and particularly well adapted for use with thin, small diametered cutting blades.
Other objects and advantages of the invention will be apparent from the following description of a preferred embodiment of the invention and from the accompanying drawings.